Machine for assembling nails and sealing washers

ABSTRACT

A machine is disclosed for applying sealing washers to nails in an automatic and rapid manner. A plurality of plungers are reciprocally mounted in bores in a block and means are provided for imparting reciprocating movement simultaneously to the plungers. Means are provided in one of the bores for positioning and retaining a nail and a washer in axial alignment therein. The plunger in the bore engages the nail head to drive its shank through the washer. The positioning means for the nail and washer are appropriately actuated by the other plungers to accomplish the operation and ultimately permit ejection of the assembled nail and washer. Means are provided for feeding a row of nails to the machine. Means are also provided for forming and feeding a row of washers to the machine. The various operations are closely integrated and carried out by means of a single driving shaft.

United States Patent Gronwald 1 51 3,707,010 [4 1 Dec. 26, 1972 s41 MACHINE FOR ASSEMIBLING NAILS AND smuuc WASHERS [72] Inventor: Walter F. Gronwald, 7680 7th Avenue, Ville St. Michel, Montreal,

Quebec, Canada [22] Filed: Nov. 9, 1970 [21] Appl. No.: 87,760

52 u.s.c1 ..10/155 511 1m. (:1. ..B23p 19/08 [58] FieldoISearch ..10/34,54,7l,l55,l55A,

527,789 10/1940 Great Britain....;. ..10/86 A Primary Examiner-Charles W. Lanham Assistant Examiner-E. M. Combs Attorney-Weir, Marshall, MacRae & Lamb [57] ABSTRACT A machine is disclosed for applying sealing washers to nails in an automatic and rapid manner. A plurality of plungers are reciprocally mounted in bores in a block and means are provided for imparting reciprocating movementsimultaneously to the plungers. Means are provided in one of the bores for positioning and retaining a nail and a washer in axial alignment therein. The plunger in the bore engages the nail head to drive its shank through the washer. The positioning means for the nail and washer are appropriately actuated by the other plungers to accomplish the operation and ultimately permit ejection of the assembled nail and washer. Means are provided for feeding a row of nails to the machine. Means are also provided for forming and feeding a row of washers to the machine.

The various operations are closely integrated and carried out by means of a single driving shaft.

12 Claims, 13 Drawing Figures PATENTED nan 2a 1912 SHEET 1 0F 4 1 N VEN TOR PATENTED DEC 26 I972 I sum 2 or 4 INVENTOR PATENT AGENT PATENTED DEC 26 m2 sum 3 or 4 iilh ' IN VEN TOR PA TENT AGENT MACHINE FOR ASSEMBLING NAILS AND SEALING WASHERS This invention relates to a machine and method for placing sealing washers on nails.

In many types of nailing operations, it is necessary that a sealing washer, usually of flexible material, be used with each nail whereby there is a seal provided between the head of the nail and the surface through which the nail is applied. The washer is applied manually or by machine over the nail shank into engagement with the head prior to use of the nail. A substantial supply of nail and washer assemblies are usually prepared prior to a particular nailing operation. Obviously, manual placement of the washers on the nails is a tedious, awkward and very time-consuming procedure.

The present invention seeks to provide a poweroperated machine having washer-forming means and to which rows of nails and washer are fed and which will automatically and successively place each washer on a nail in a very rapid manner.

The machine comprises a block having first, second and third bores therein and a plunger reciprocally mounted in each bore. Means are provided for reciprocating the plungers simultaneously. Springpressed washer-positioning slides extend into the first bore for positioning and retaining a washer in the bore. Also, spring-pressed nail-positioning slides extend into the first bore intermediate the plunger therein and the washer-positioning slides for positioning and retaining a nail in the bore. The nail-positioning slides are initially engageable by the plungers in the second and third bores during the downward stroke thereof to withdraw these slides from the first bore. The washerpositioning slides are subsequently engageable by the plungers in the second and third bores during the downward stroke thereof to withdraw these slides from the first bore. The plunger in the first bore engages the nail in the downward stroke while the nail is being held by the positioning slides and drives it through the washer while the latter is being held by its positioning slides. Withdrawal of the both sets of slides from the first bore permits the assembled nail and washer to drop out of the first bore.

The invention will be described with reference to the accompanying drawings, in which:

FIG. 1 is a side elevation of the machine in accordance with the invention,

FIG. 2 is a plan view, partly in section, of the machine,

FIG. 3 is an enlarged sectional view on line 3--3 of FIG. 2,

FIG. 4 is an enlarged side elevation of a portion of the machine,

FIGS. 5, 6 and 7 are enlarged sectional plan views of a portion of the machine showing sequential positions of parts in the nail feeding procedure,

FIG. 8 is a perspective view of one of the nail-engaging parts shown in FIGS. 5, 6 and 7.

FIGS. 9, 10 and 11 are enlarged sectional end elevations of a portion of the machine showing sequential operating positions of the plungers and slides,

FIG. 12 is an enlarged sectional plan view taken on line 12-12 of FIG. 9 of portions of the washer-positioning slides, and

FIG. 13 is an enlarged side elevation of a portion of the machine showing tube feeding means in the washer forming device.

In the drawing, the machine is-shown as mounted on a base 10. Power is supplied by means of a shaft 11 driven by any suitable source of motive power.

Fixed to the shaft 11 is a disc 12 having a crank pin 13 and arranged to apply vertical reciprocating movement to a rod 14 by means of a connecting rod 15 and wrist pin 16 on member 17 fixed to rod 14. Rod 14 is supported for reciprocating movement in bearings 18 mounted on a fixed frame member 19.

Rod 14 has an arm 20 fixed to its lower end and carrying, for reciprocation therewith, a nail-engaging plunger 21, cam slide-actuating plungers 22,23 (one on each side of plunger 21), latching bar 24, and latch release bar 25 (FIG. 3). The members 21 to 25 have parallel axes of movement and are generally laterally aligned (FIG. 2').

The plungers 21,22,23 are reciprocally mounted in bores 26,27,28 in a block 29. Block 29 has a slot or recess 30 leading into bore 26 of plunger 21. The top surface of the opposed walls of the slot is countersunk at 31 to receive the end portion of an inclined nail feeder trough 32 (FIGS. 1 and 5)having a bottom slot 33 coinciding with the slot 30. It will be apparent that the feeder 32 is designed to feed nails 34 in single row file with the head of each nail resting on the top surface of the slot walls and the shank depending into the slot.

When the leading nail reaches the position shown in FIG. 5, the shank 35 thereof engages the inclined end surface 36 of a slide 37 reciprocally mounted in block 29. A spring 38 urges the slide 37 into the position shown with end surface 36 extending into slot 30 for engagement by the nail shank.

In alignment with slide 37 is a second slide 39 reciprocally mounted in block 29 and having an inclined end surface 40 in confronting relation to end surface 36. Slide 39 is urged by a spring 41 towards slide 37 but is latched against the action of the spring to the position of FIG. 4 wherein its end surface 40 is clear of slot 30. The latch means (FIG. 3) comprises a shoulder 39a on the slide 39 and a latch 42 having a latching recess 43 for reception of shoulder 41. Latch 42 is pivotally carried by a frame 44 fixed to block 29. A spring 45 urges the latch into locking position.

It will be apparent that release of latch 42 will cause slide 39 to move towards slide 37 under the action of spring 41. The end surfaces 36 and 40 will initially assume the position of FIG. 6 in which the shank 35 is engaged by both surfaces. However, surface 40 is at an angle with the side surface of slide 39 less than the angle of surface 36 with the aligned side surface of slide 37 whereby only an end of surface 40 engages a point on surface 36 when the slides meet in the position of FIG. 7. In result, the shank 35 is ejected or squeezed out of the end of slot 30 by the coacting surfaces 36 and 40 and into the bore 26. As shown in FIG. 7 in the terminal position of slide 39, surfaces 36 and 40 provide walls diverging into the bore 26.

Means are provided for ensuring that the nail assumes a vertical axial position for effective handling by the slides 37 and 39 and comprises an arm 96 fixed to shoulder 42 and having a cam surface 97 engageable with the shank of the nail to place it in vertical alignment.

Means are provided for releasably holding each nail as it is deposited in bore 26. This means comprises a pair of aligned slides 46 (FIGS. 9,10,11) mounted for l060l2 000i reciprocation in block 29 along an axis intersecting that of bore 26. Each slide 46 is urged by a spring 47 towards the other whereby the opposed end surfaces 48 are disposed with the bore and in the position shown in FIG. 9. Each surface 48 has an inclined shoulder 49 for engagement by the head of a nail. The shoulder leads to a surface 50, such surfaces 50 being spaced apart only sufficiently to permit easy reception therebetween of the nail shank.

Means are provided for axially positioning a washer 51 in bore 26. This means comprises a pair of aligned slides 52 mounted for reciprocation in block 29 also .along an axis intersecting that of bore 26 and on a level below that of slides 46. Each slide is urged by a spring 53 towards the other into the position shown in FIGS. 9 and 12 wherein a shoulder 54 on the confronting end of each slide projects into the bore. The confronting end surface of each slide has an arcuate seating surface 55 to position the washer in axial relation in the bore.

Means for making and feeding washers in single file into the bore 26 comprises a channel 56 leading into bore 26 and having a flat bottom surface 57 in the plane of the washer supporting surfaces of shoulders 54. The channel extends into a frame member 58 fixed to block 29. The channel has a width suflicient only to receive a single row of washers, i.e., it is slightly wider than the diameter of a washer (FIG. The row of washers is adapted to be fed towards the bore 26 by a stream of air led into the outer end of the channel by an air hose 59 supplied with compressed air by a line 60 from any suitable source. A valve 61 in hose 59 is periodically opened, under the action of a cam 62 on disc 12, to provide bursts of washer feeding air.

.Washers are cut from a flexible tubing 63 and deposited into the outer end of the channel 56 at a fixed and constant rate.

To this end, tubing 63 (FIGS. 1,4,13) is fed in fixed increments of movement through a bore 64 in a block 65 fixed, to and surmounting frame member 58. As shown in FIG. 4, a recess 66 is provided directly above the entrance portion of channel 56 and the end of tubing 63 extends into the recess. A knife 67, mounted for reciprocating movement in a direction normal to the axis of the tubing, is arranged to sever washers from the tubing, each severed washer dropping successively into the entrance of the channel 56 for movement therealong under air pressure.

' Means for imparting reciprocating movement to the knife 67 comprises a plate 68 slidingly mounted on a base 69 and to which the knife is fixed. The knife is shown as being a disc with a circular cutting edge 70 so that as each minor cutting section thereof becomes dull, the knife may be readily loosened, rotated to present a sharp cutting section, and fixed in place again. However, any suitable knife blade may be provided.

A connecting rod 71 has one end connected to a wrist pin 72 on a bracket 73 fixed to plate 68 and its other end connected to a crank pin 74 on a disc 75 rotatably mounted in a bearing 76 and driven by a sprocket 77, chain 78, and sprocket 79 on driven shaft 1 1 After each tubing severing operation, an increment of axial movement is applied to the tubing to position it in place for the next severing stroke of the knife. Means therefor comprises a pair of wheels 80 mounted on shafts 81 in block 65 and having knurled peripheries extending a slight distance into bore 64 for nipping engagement therebetween of a portion of the tubing. Intermeshing gears 82 on shafts 81 impart simultaneous rotating movement in opposite directions to the wheels 80. One of the shafts 81 is driven through a clutch 83. Braking force is applied to this shaft to prevent backlash by means of a disc 84 fixed to the shaft, a pin 85 mounted for axial movement in block 65 and having its end engaging the periphery of the disc 84, and a flat spring 86 (FIG. 2) applying pressure to the head of the pin.

Clutch 83 is periodically actuated to periodically apply an increment of rotative movement to the wheels 80 by' means of a connecting rod 87 pivotally connected to clutch 83 at 88 and to a link 89 at 90, link 89 being pivotally carried at 91 on a fixed frame member v92. Connecting rod 87 is biased in one direction by a spring 93 and is moved in the opposite direction against the action of the spring in response to each return stroke of the knife plate 68. This movement is effected by a pin 94 engaging link 89and carried by an arm 95 fixed to bracket 73. It will thus be apparent thateach return stroke of the knifeplate results in the application of an increment of movement to tubing 63 to place it in position for severance therefrom of a washer 51.

As shown, the pin 94 has screw-threaded adjustment with respect to arm 95 to vary, as desired, the stroke of the connecting rod 87 and thus the extent of each increment of movement of the tubing I 63 and the thickness of the washer 51. v

Returning now to operation of the machine, as more particularly illustrated in FIGS. 3, 9, 10 and 11, it may be assumed that a nail 33 and a washer 51 have been positioned in bore 26, and that rod 14 with arm 20 is commencing a downward stroke, as shown in FIG. 9. The plunger 21 will engage the head of the nail 33 and move it downwardly through the bore. Preferably, the plunger 21 is provided with resilient shock-absorbing means such as a spring-pressed tip portion 98.

The nail shank will move initially between surfaces 50 of slides 46 and then through the axial opening in the washer 51. Further movement of the nail will cause its head to move between slides 46 into proximity or engagement with shoulders 49.

At this time, the tips of plungers 22,23 will enter bores 99 in the slides 46. Tip 100,101 of plungers 22 ,23 has a frusto-conical shape to provide an inclined cam surface thereon. Each bore 99 has a diverging mouth or frusto-conical cam surface 102 for engagement by a cam surface 100,101. The diameter of cam surface 102 throughout its extent is greater than the maximum diameter of plunger 22,23 and, in the spring-held position of the slides 46, the circumferential edge of each bore 99 is located in substantially tangential relation with respect to the circumferential edge of bore 27,28 at a point remote from bore 26.

Interengagement of cam surfaces 100,101 and 102 as a result of downward movement of plungers 22,23 will, therefore, apply sliding movement to slides 46 to further separate their end surfaces 49,50 and permit the nail with its head to move downwardly under the action of plunger 21 to the position of FIG. 9 where the head of the nail has engaged the washer 51, i.e., the desired positioning of the washer on the nail.

At this time, the tips of plungers 22,23 will enter bores 103 in slides 52. Each bore 103 has a diverging mouth or frusto-conical cam surface 104 for engagement by the cam surface 100,101 of plungers 22,23. It will be apparent that bores 103 are of the same dimensions as bores 99 in slides 46 and are similarly positioned in slides 52. Thus, interengagement of cam surfaces l00,101 and 104 as a result of downward movement of the plungers 22,23 will apply sliding movement to slides 52 to further separate shoulders 54, freeing the washer and nail head from support thereby and permitting the nail and washer to drop out of the machine, as shown in FIG. 11. Suitable collecting means (not shown) for the assembled articles are provided.

The downward stroke of rod 14 also results in resetting of the latch 42. Latching bar 24 has an inclined cam surface 105 (FIG. 3) engageable with a complementary surface 106 on shoulder 39a to slide it and slide 39 away from slide 37 to a point where latch 42 drops into latching relation therewith (FIG. 3).

Upward stroke of rod 14 will result in slides 46 and 52 returning to their spring-held positions (FIG. 9) and will result in unlatching of latch 42 by latch release bar 25, thus causing another nail to be properly positioned in bore 26.

There has thus been provided a substantially fully automatic machine for effective assembly of nails and washers in an extremely rapid manner. A machine in accordance with the invention has been found to produce 150 to 200 assembled nails and washers per minute.

Various changes may be made as desired in the structural details of the machine. For instance, instead of the cylindrical plungers 22,23, these may be in the form of bars having inclined cam surfaces similar in form to latching bar 24.

I claim:

1. A machine for assembling nails and sealing washers which comprises a block having first, second and third parallel bores therein, a plunger mounted for reciprocation in and extending through one end of each of said bores, means for reciprocating said plungers simultaneously in said bores in upward and downward strokes therein, spring-pressed washer-positioning slides extending into said first bore and between said second and third bores for positioning and retaining a washer in axial alignment within said first bore, and spring-pressed nail-positioning slides extending into said first bore and between said second and third bores intermediate said plunger therein and said WASHER- positioning slides for positioning and retaining a nail in axial alignment within said first bore for engagement by said plunger therein, said nail-positioning slides being initially engageable by said plungers in said second and third bores during said downward stroke thereof to withdraw said nail-positioning slides from said first bore thereby releasing said nail for insertion through said washer as said plunger in said first bore continues said downward stroke, said washer-positioning slides being subsequently engageable by said plungers in said second and third bores during a continuation of said downward stroke thereof to withdraw said washer-positioning slides from said first bore thereby releasing a nail and washer assembly for ejection from said machine.

2. A machine for assembling nails and sealing washers as defined in claim 1, said block having a nail head path leading to said first bore, said path having a slot for reception of nail shanks, means for feeding a single row of nails along said path, and means for successively ejecting nails from said path into said first bore.

3. A machine for assembling nails and sealing washers as defined in claim 2, said ejecting means comprising a first spring-pressed slide having an inclined end surface disposed in said path, a second springpressed slide having an inclined end surface confronting said first inclined end surface and having an angle of inclination less than that of said first surface, latch means mounted on said block for holding said second slide out of said path, a latch release bar carried by said plunger reciprocating means and operable during said upward stroke thereof to release said latch means and cause engagement of said inclined end surfaces, and a latching bar carried by said plunger reciprocating means and operable during said downward stroke thereof to apply said latch means.

4. A machine for assembling nails and sealing washers as defined in claim 1, each said nail-positioning slide having an end surface in confronting relation to an end surface on the other of said slides, said confronting surfaces having spaced nail head-receiving portions and spaced nail shank-receiving portions, the space between said shank-receiving portions being less than the space between said head-receiving portions, each said nail-positioning slide having a plunger-receiving bore in normally offset relation to one of said second and third bores, each of said slide bores having a diverging mouth surface, each of said plungers in said second and third bores having an inclined end surface engageable with one of said diverging mouth surfaces to impart sliding movement to said nail-positioning slides.

5. A machine for assembling nails and sealing washers as defined in claim 4, each said washer-positioning slide having an end surface in confronting relation to the other of said slides, said confronting surfaces having washer-supporting shoulders, each said washerpositioning slide having a plunger-receiving bore in normally offset relation to one of said second and third bores, each of said washer-positioning slide bores having a diverging mouth surface engageable by said inclined end surface to one of said plungers to impart sliding movement to said washer-positioning slides.

6. A machine for assembling nails and sealing washers as defined in claim 1, including means for feeding washers into said first bore, including a frame member, said frame member and said block having a channel leading to said bore, and means for periodically directing bursts of air into said channel to impart movement to a row of washers in said channel.

7. A machine for assembling nails and sealing washers which comprises:

a block having first, second and third parallel bores therein;

a plunger mounted for reciprocation in and extending through one end of each of said bores;

drive means for reciprocating said plunger simultaneously in said bores in upward and downward strokes therein;

spring-pressed washer-positioning slides extendinginto said first bore and between said second and third bores for axially aligning and retaining a washer in said first bore;

spring-pressed nail-positioning slides extending into said first bore and between said second and third bores intermediate said plungers and said washerpositioning slides for axially aligning and retaining a nail in said first bore;

said nail-positioning slides being initially engageable by said plungers in said second and third bores during said downward stroke thereof to withdraw said nail-positioning slides from said first bore thereby releasing said nail for insertion through said washer as said plunger in said first bore continues said downward stroke, said washer-positioning slides being subsequently engageable by said plungers in said second and third bores during a continuation of said downward stroke thereof to withdraw said washer-positioning slides from said first bore thereby releasing a nail and washer assembly for ejection from said machine;

means mounted on said block for forming and depositing said washers in said first bore, said means comprising flexible tube holding and advancing means, a reciprocating knife adapted to cut a washer from a flexible tube advanced perpendicular thereto by said holding and advancing means; said holding and advancing means and said reciprocating knife being operatively connected to said drive means and synchronized therewith so as to provide a washer in said first bore on each downward stroke of said plunger therein.

8. A machine for assembling nails and washers as claimed in claim 7 including: a channel adjacent said reciprocating knife and communicating with said first bore adapted to receive said washers, and means operatively connected to said drive means for periodically directing air bursts into said channel to transport said washers to said first bore.

9. A machine for assembling nails and sealing washers as defined in claim 8, said tube advancing means comprising a pair of knurled rollers mounted in said frame member and having a tube-receiving nip, gears connecting said rollers for simultaneous rotation in opposite directions, a driving shaft for one of said rollers, clutch means on said driving shaft, an arm connected to said clutch means and operable to periodically rotate said driving shaft, and means fixed to said plate to impart operating movement to said arm during the return stroke of said plate and knife.

10. A machine for assembling nails and sealing washers as defined in claim 7, said knife comprising a disc having a circular peripheral cutting edge.

11. A machine for assembling nails and sealing washers as defined in claim 8, said means for directing bursts of air into said channel comprising a tube for connection to a supply of air under pressure, a valve in said tube, and a valve-actuating cam on said drive means.

12. A machine for assembling nails and sealing washers as defined in claim 3, said second springpressed slide having a nail-aligning arm connected thereto, said arm having an end cam surface disposed in said path when said end surface of said second spring-pressed slide 18 in said path and engageable with a nail shank to align it axially in said first bore.

l II! t t 

1. A machine for assembling nails and sealing washers which comprises a block having first, second and third parallel bores therein, a plunger mounted for reciprocation in and extending through one end of each of said bores, means for reciprocating said plungers simultaneously in said bores in upward and downward strokes therein, spring-pressed washer-positioning slides extending into said first bore and between said second and third bores for positioning and retaining a washer in axial alignment within said first bore, and spring-pressed nail-positioning slides extending into said first bore and between said second and third bores intermediate said plunger therein and said WASHERpositioning slides for positioning and retaining a nail in axial alignment within said first bore for engagement by said plunger therein, said nail-positioning slides being initially engageable by said plungers in said second and third bores during said downward stroke thereof to withdraw said nail-positioning slides from said first bore thereby releasing said nail for insertion through said washer as said plunger in said first bore continues said downward stroke, said washer-positioning slides being subsequently engageable by said plungers in said second and third bores during a continuation of said downward stroke thereof to withdraw said washer-positioning slides from said first bore thereby releasing a nail and washer assembly for ejection from said machine.
 2. A machine for assembling nails and sealing washers as defined in claim 1, said block having a nail head path leading to said first bore, said path having a slot for reception of nail shanks, means for feeding a single row of nails along said path, and means for successively ejecting nails from said path into said first bore.
 3. A machine for assembling nails and sealing washers as defined in claim 2, said ejecting means comprising a first spring-pressed slide having an inclined end surface disposed in said path, a second spring-pressed slide having an inclined end surface confronting said first inclined end surface and having an angle of inclination less than that of said first surface, latch means mounted on said block for holding said second slide out of said path, a latch release bar carried by said plunger reciprocating means and operable during said upward stroke thereof to release said latch means and cause engagement of said inclined end surfaces, and a latching bar carried by said plunger reciprocating means and operable during said downward stroke thereof to apply said latch means.
 4. A machine for assembling nails and sealing washers as defined in claim 1, each said nail-positioning slide having an end surface in confronting relation to an end surface on the other of said slides, said confronting surfaces having spaced nail head-receiving portions and spaced nail shank-receiving portions, the space between said shank-receiving portions being less than the space between said head-receiving portions, each said nail-positioning slide having a plunger-receiving bore in normally offset relation to one of said second and third bores, each of said slide bores having a diverging mouth surface, each of said plungers in said seCond and third bores having an inclined end surface engageable with one of said diverging mouth surfaces to impart sliding movement to said nail-positioning slides.
 5. A machine for assembling nails and sealing washers as defined in claim 4, each said washer-positioning slide having an end surface in confronting relation to the other of said slides, said confronting surfaces having washer-supporting shoulders, each said washer-positioning slide having a plunger-receiving bore in normally offset relation to one of said second and third bores, each of said washer-positioning slide bores having a diverging mouth surface engageable by said inclined end surface to one of said plungers to impart sliding movement to said washer-positioning slides.
 6. A machine for assembling nails and sealing washers as defined in claim 1, including means for feeding washers into said first bore, including a frame member, said frame member and said block having a channel leading to said bore, and means for periodically directing bursts of air into said channel to impart movement to a row of washers in said channel.
 7. A machine for assembling nails and sealing washers which comprises: a block having first, second and third parallel bores therein; a plunger mounted for reciprocation in and extending through one end of each of said bores; drive means for reciprocating said plunger simultaneously in said bores in upward and downward strokes therein; spring-pressed washer-positioning slides extending into said first bore and between said second and third bores for axially aligning and retaining a washer in said first bore; spring-pressed nail-positioning slides extending into said first bore and between said second and third bores intermediate said plungers and said washer-positioning slides for axially aligning and retaining a nail in said first bore; said nail-positioning slides being initially engageable by said plungers in said second and third bores during said downward stroke thereof to withdraw said nail-positioning slides from said first bore thereby releasing said nail for insertion through said washer as said plunger in said first bore continues said downward stroke, said washer-positioning slides being subsequently engageable by said plungers in said second and third bores during a continuation of said downward stroke thereof to withdraw said washer-positioning slides from said first bore thereby releasing a nail and washer assembly for ejection from said machine; means mounted on said block for forming and depositing said washers in said first bore, said means comprising flexible tube holding and advancing means, a reciprocating knife adapted to cut a washer from a flexible tube advanced perpendicular thereto by said holding and advancing means; said holding and advancing means and said reciprocating knife being operatively connected to said drive means and synchronized therewith so as to provide a washer in said first bore on each downward stroke of said plunger therein.
 8. A machine for assembling nails and washers as claimed in claim 7 including: a channel adjacent said reciprocating knife and communicating with said first bore adapted to receive said washers, and means operatively connected to said drive means for periodically directing air bursts into said channel to transport said washers to said first bore.
 9. A machine for assembling nails and sealing washers as defined in claim 8, said tube advancing means comprising a pair of knurled rollers mounted in said frame member and having a tube-receiving nip, gears connecting said rollers for simultaneous rotation in opposite directions, a driving shaft for one of said rollers, clutch means on said driving shaft, an arm connected to said clutch means and operable to periodically rotate said driving shaft, and means fixed to said plate to impart operating movement to said arm during the return stroke of said plate and knife.
 10. A machine for assembling nails and sealing washers as defined in Claim 7, said knife comprising a disc having a circular peripheral cutting edge.
 11. A machine for assembling nails and sealing washers as defined in claim 8, said means for directing bursts of air into said channel comprising a tube for connection to a supply of air under pressure, a valve in said tube, and a valve-actuating cam on said drive means.
 12. A machine for assembling nails and sealing washers as defined in claim 3, said second spring-pressed slide having a nail-aligning arm connected thereto, said arm having an end cam surface disposed in said path when said end surface of said second spring-pressed slide is in said path and engageable with a nail shank to align it axially in said first bore. 